Chaparral being type-converted to weedy, non-native grassland. This site is east of the Viejas Casino off Interstate 8 in San Diego County. The far left shows 34 year old chaparral last burned during the 1970 Laguna fire. The middle/left of the picture shows an area recovering from the Viejas fire of January 3, 2001. It is composed primarily of chamise, deerweed, and several other shrub species. To the right is a portion of the Viejas fire scar reburned in the Cedar fire October, 2003. As you can see the Cedar fire scar is now filled with non-native grasses. The majority of the resprouting shrubs have been killed and no obligate seeding species, such as Ceanothus, are present. The interval between the two fires was too short, causing the elimination of the chaparral plant community.
WHAT IS TYPE CONVERSION?
A common misconception is that since chaparral is a fire-adpated plant community, it needs to burn and fire serves as a force of renewal. Nothing could be further from the truth. Chaparral is not a simple, homogenous ecosystem. Each type of chaparral responds differently to fire depending on species present, angle and direction of the slope on which it grows, and climatic conditions. The one factor all types of chaparral have in common, however, is that they are all sensitive to fire intervals shorter than 15-20 years. This is the time it takes for a burned stand to recover properly and set enough seed in the soil to be able to bounce back after the next fire. As fire frequencies increase due to human caused ignitions, the intervals between fires have been contracting causing the complete elimination of chaparral in some areas and serious degradation in others.
As can be seen in the photo above, non-native grasses quickly invade frequently burned areas helping to prevent chaparral from returning. One large area that can be seen demonstrating this principle is near Highway 52 in San Diego County next to Miramar Marine Air Station. What was once a pristine stand of chamise chaparral is now being type-converted to non-native, weedy grassland. The recent Cedar fire probably sealed much of the area's fate.
See our Desert Fires page for details concerning type-conversion in desert ecosystems.
For information concerning the type conversion of areas near communities due to excessive fire clearance activity please see our Protecting your home page.
* * * * * * * * * * * *
Please see our National Chaparral Recreation Plan that changes how the four National Forests in Southern California are classified and managed in order to better protect the chaparral ecosystem and to help all Americans develop a more rewarding connection with nature.
Type conversion in the Trabuco Ranger District of the Cleveland National Forest. This is a fuel break along the ridgeline of the Santa Ana Mountains. All native vegetation has been eliminated by crushing and repeated fire. The effectiveness of this type of habitat elimination in terms of preventing the spread of wildfires is highly questionable because ridgelines are natural fire breaks themselves. The natural resource damage is unquestionably significant.
Morrell Canyon above Lake Elsinore in the Cleveland National Forest. Congressman Darrell Issa and a Nevada corporation want to build a dam here. Photo: Andrew Harvey/Lighthawk
Taking of our Natural Heritage
A number of projects planned in southern California are seriously challenging the promise that natural landscapes set aside for our families to enjoy nature will always be there for them: a toll road through San Onofre State Beach, a high voltage electrical power line across Anza-Borrego State Park, and the damming of Morrell Canyon in the Cleveland National Forest next the San Mateo Wilderness above Lake Elsinore.
The damming of Morrell Canyon (see photo above) is of particular concern to us because of the pristine nature of the chaparral habitat preserved in the canyon and the opportunities the canyon provides for families to enjoy California nature in its pure form. Morrell Canyon is a beautiful and popular hiking area on the Cleveland National Forest. However, a private energy company based in Nevada is proposing to drown the canyon behind a 180-foot dam. Accompanying the project would be 190-foot-tall transmission towers and power lines across miles of the forest.
Read the full details of this proposed dam from the Federal Energy Regulatory Commission. The project is officially called the Lake Elsinore Advanced Pumped Storage (LEAPS) Project.
THE THREAT OF INVASIVE PLANTS
Hawaii as a Case Study.
Could California Chaparral suffer the same fate?
Just how big is the noxious weed problem? In 1995, for every acre of federal land lost to forest fires, we lost two acres to noxious weeds. This problem affects all 50 states, but nowhere is it more serious than in Hawaii. Because of our climate, Hawaii is heaven-on-earth, for weeds. This year for the first time, foreign introduced plants outnumber Hawaii's rich heritage of native species. Hawaii is the Aloha State, but we have no aloha for alien weeds. We need to start thinking of noxious weeds as biological pollution.
U.S. SENATOR DANIEL AKAKA, Hawaii
Pacific Currents: Lush Hawaii is a zone of mass extinction
Monday, October 9, 2000
By WILLIAM ALLEN ST. LOUIS POST-DISPATCH
KAILUA KONA, Hawaii -- Tourists walking the beaches, streets and parks of resort towns like this one see an impressive array of lush vegetation and a kaleidoscope of birds.
Exotic-looking papaya and banyan trees, beautiful blossoms of bougainvillea and the sweet smell of jasmine are everywhere. Canaries, cardinals and Saffron finches flitter about.
But this perfect tropical paradise holds a dark secret: None of these plants or animals is native to Hawaii.
Contrary to the myth, when vacationers come to the Hawaiian Islands, they unknowingly enter a zone of mass extinction, not Eden.
The real Hawaii has become the biggest ecological catastrophe in the United States -- the nation's capital of species extinction and endangerment, scientists say. And this disaster is playing out in the tropical jewel of the United States unnoticed by the American public.
Hawaii, the nation's leader in biological diversity, is well on its way to becoming an archipelago of the "living dead." That's a term biologists use to describe a species of animal or plant that still has a few individuals alive but which almost surely will go extinct soon.
Invasion by non-native species, economic development, suburban sprawl, even environmental destruction by hooved animals -- all these have added up to devastation for native animals, plants and the ecological connections that bind them, scientists say. In turn, this threatens the fragile tapestry of life on the islands, its supply of fresh water, its soil and its economic future. To read more go here.
Nonnative grasses have altered the natural fire cycle in Hawaii
In contrast to many other terrestrial environments of the world, fire does not seem to have played an important evolutionary role in most native ecosystems of the Hawaiian islands, and relatively few Hawaiian endemic plant species possess adaptations to fire. Since lightning is uncommon on oceanic islands, humans cause most fires in Hawaii. Nonnative grasses primarily fuel these fires, which are generally highly destructive to native plants.
The major grasses that fuel fires in Hawaii are beardgrass, broomsedge, buffel grass, fountain grass, and molassesgrass. Invasion by these grasses into otherwise undisturbed native ecosystems adds enough fine fuel to carry fire into previously fire-free sites. Most native species are eliminated sooner or later by fire, while invasive grasses recover rapidly after fire. This increases the flammability of the site and the dominance of invasive grasses. To read more go here.
DON'T PLANT A PEST!
Give them an inch and they'll take an acre...
Download below the California Native Plant Society's and California Invasive Plant Council's Invasive plant brochure that will help you identify plants that should not be planted in your garden and suggested alternatives.
Go here to download the printable Don't Plant A Pest brochure here. This is a large PDF file (4 MB) and may take a few minutes to download on a dial-up connection. It has been formatted to print on standard 8 1/2" by 11" paper. The Southern California Don't Plant a Pest website is under construction, so please check this space soon for even more recommended alternatives.
This brochure describes alternatives for the following invasive plants:
Iceplant/hottentot fig (Carpobrotus edulis)
Ivy (Hedera spp.)
Periwinkle (Vinca major)
Pampas grass (Cortaderia selloana)
Fountain grass (Pennisetum setaceum)
Scotch, French, Portugese, bridal, and Spanish brooms
Acacia/western coastal wattle (Acacia cyclops)
Myoporum (Myoporum laetum)
Mexican fan palm (Washingtonia robusta)
Canary island date palm (Phoenix canariensis)
Brazilian pepper tree (Schinus terebinthifolius)
Blue-gum and red-gum eucalyptus (Eucalyptus globulus, E. camuldulensis)
Print copies of this brochure (9" x 21" accordion-fold brochure) can be ordered from the Mission Resource Conservation District. Download the order form here, fill it out and return with payment to: Mission RCD WMA program, PO Box 1777, Fallbrook, CA 92088-1777. You can also order by calling Mission RCD at 760-943-6924. Copies of this and other brochures are also available through the California Invasive Plant Council.
